wiki: add Carbon Design System icons (2673) + pictograms (1000)

- 2673 SVG icons from @carbon/icons v11.82.0 (~2.5 MB)
- 1000 SVG pictograms from Carbon Design System (~2.0 MB)
- Updated 00-overview.md with asset structure and category listing

All icons: 32x32, fill: currentColor, optimized SVG
All pictograms: 24x24, fill: currentColor, SVG

assets/icons/carbon/accumulation-rain.svg

@@ -0,0 +1 @@
+<svg id="Layer_1" data-name="Layer 1" width="32" height="32" viewBox="0 0 32 32"> <path d="M28,4a2.0023,2.0023,0,0,0-2,2V8H24a3.4376,3.4376,0,0,1-3.0513-2.3164A1.007,1.007,0,0,0,20,5a.9894.9894,0,0,0-.9468.6787A3.44,3.44,0,0,1,16,8a3.4376,3.4376,0,0,1-3.0513-2.3164A1.007,1.007,0,0,0,12,5a.971.971,0,0,0-.9468.6787A3.44,3.44,0,0,1,8,8H6V6A2.0023,2.0023,0,0,0,4,4H2V6H4V26a2.0023,2.0023,0,0,0,2,2H26a2.0023,2.0023,0,0,0,2-2V6h2V4ZM6,26V22h4V20H6V16h4V14H6V10H8a4.9316,4.9316,0,0,0,4-1.9873,5.0192,5.0192,0,0,0,8,0A4.9316,4.9316,0,0,0,24,10h2V26Z" transform="translate(0 0)"/> </svg>